> To be fully compliant, we have to handle the worst case, which means a full-size buffer for a jumbo frame.
Well, fully compliant except for IPv6. If you said no jumbo frames for PTP, or no jumbo frames for specifically IPv6 PTP, then the extra buffer for PTP checksums only needs 4% of your SRAM.
> They may also be tucked between other packets.
Does that matter? Let's say a particular PTP packet is 500 bytes. If there's a packet immediately after it, I would expect it to flow through the extra buffer like it's a 500 byte shift register.
Well, fully compliant except for IPv6. If you said no jumbo frames for PTP, or no jumbo frames for specifically IPv6 PTP, then the extra buffer for PTP checksums only needs 4% of your SRAM.
> They may also be tucked between other packets.
Does that matter? Let's say a particular PTP packet is 500 bytes. If there's a packet immediately after it, I would expect it to flow through the extra buffer like it's a 500 byte shift register.